/* =========================
   Reset básico
========================= */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* =========================
   Body 
========================= */
body {
  font-family: 'Inter', sans-serif;
  background: linear-gradient(135deg, #E9E0E7, #F0F5F9);
  color: #333333;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  align-items: center;
}

/* =========================
   Header
========================= */
header {
  text-align: center;
  padding: 2rem 1rem;
}

header h1 {
  font-family: 'Poppins', sans-serif;
  font-weight: 700;
  font-size: 2.5rem;
  background: linear-gradient(90deg, #FF9ACD, #BDE0FE);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* =========================
   Tarjetas principales
========================= */
main {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  width: 90%;
  max-width: 800px;
  margin-bottom: 2rem;
}

/* Tarjeta Intro */
.intro {
  background: #FFFFFF;
  padding: 2rem;
  border-radius: 20px;
  box-shadow: 0 10px 20px rgba(0,0,0,0.08);
  text-align: center;
}

.intro h2 {
  font-family: 'Poppins', sans-serif;
  font-size: 1.5rem;
  color: #A0C4FF;
  margin-bottom: 0.5rem;
}

.intro p {
  font-size: 1rem;
  color: #555555;
}

/* Tarjeta Opciones */
.options {
  display: flex;
  justify-content: center;
  gap: 1rem;
}

.time-btn {
  padding: 1rem 2rem;
  font-size: 1.2rem;
  border: none;
  border-radius: 30px;
  background: #f8cbdc;
  color: #4c4a4a;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 6px 15px rgba(0,0,0,0.1);
}

.time-btn:hover {
  background-color: #d5c7d8;
  color: #FFFFFF;
  transform: scale(1.08);
}

/* Tarjeta Visual */
.visual {
  background: #FFFFFF;
  padding: 1rem;
  border-radius: 20px;
  box-shadow: 0 10px 20px rgba(0,0,0,0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  height: 300px;
}

.animation-area {
  width: 120%;
  height: 100%;
  background: linear-gradient(135deg, #BDE0FE, #FFC8DD);
  border-radius: 15px;
}

/* Tarjeta Botón iniciar */
.start {
  display: flex;
  justify-content: center;
}

.start #start-btn {
  padding: 1rem 2.5rem;
  font-size: 1.2rem;
  border: none;
  border-radius: 30px;
  background: #A0C4FF;
  color: #FFFFFF;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 8px 20px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
}

.start #start-btn:hover {
  background: #FF9ACD;
  transform: translateY(-3px);
}

/* =========================
   Footer
========================= */
footer {
  text-align: center;
  padding: 1rem;
  font-size: 0.9rem;
  color: #555555;
}

/* =========================
   Animación respiración
========================= */
.animation-area::before {
  content: '';
  display: block;
  width: 100px;
  height: 100px;
  background: radial-gradient(circle, #A0C4FF, #BDE0FE);
  border-radius: 50%;
  animation: breathe 4s ease-in-out infinite;
}

@keyframes breathe {
  0% {
    transform: scale(1);
    opacity: 0.7;
  }
  50% {
    transform: scale(1.4);
    opacity: 1;
  }
  100% {
    transform: scale(1);
    opacity: 0.7;
  }
}

/* Ondas concéntricas */
.animation-area::before,
.animation-area::after {
  content: '';
  position: absolute;
  width: 100px;
  height: 100px;
  border-radius: 50%;
  border: 2px solid rgba(160,196,255,0.5);
  animation: pulse 4s ease-in-out infinite;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

.animation-area::after {
  animation-delay: 2s;
}

@keyframes pulse {
  0% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 0.7;
    border-color: rgba(160,196,255,0.5);
  }
  50% {
    transform: translate(-50%, -50%) scale(2);
    opacity: 0;
    border-color: rgba(189,224,254,0.3);
  }
  100% {
    transform: translate(-50%, -50%) scale(1);
    opacity: 0.7;
    border-color: rgba(160,196,255,0.5);
  }
}

.animation-area {
  position: relative;
  overflow: hidden;
}

.particle {
  position: absolute;
  width: 10px;
  height: 10px;
  background: #FFC8DD;
  border-radius: 50%;
  opacity: 0.6;
  animation: float 6s linear infinite;
}

.particle1 { top: 20%; left: 30%; animation-delay: 0s; }
.particle2 { top: 50%; left: 70%; animation-delay: 2s; }
.particle3 { top: 80%; left: 40%; animation-delay: 4s; }

@keyframes float {
  0% { transform: translateY(0) translateX(0); opacity: 0.6; }
  50% { transform: translateY(-30px) translateX(20px); opacity: 1; }
  100% { transform: translateY(0) translateX(0); opacity: 0.6; }
}

.animation-area::before {
  background: radial-gradient(circle, #A0C4FF, #BDE0FE);
  animation: breathe 4s ease-in-out infinite, colorShift 8s ease-in-out infinite;
}

@keyframes colorShift {
  0% { background: radial-gradient(circle, #A0C4FF, #BDE0FE); }
  50% { background: radial-gradient(circle, #FFC8DD, #FF9ACD); }
  100% { background: radial-gradient(circle, #A0C4FF, #BDE0FE); }
}

.motivational {
  position: absolute;
  bottom: 110px;
  width: 100%;
  text-align: center;
  font-family: 'Poppins', sans-serif;
  font-weight: 800;
  font-size: 1.8rem; 
  color: #fbf9fa;
  opacity: 0;
  animation: fadeInOut 6s ease-in-out infinite;
}

@keyframes fadeInOut {
  0%, 20% { opacity: 0; }
  30%, 70% { opacity: 1; }
  80%, 100% { opacity: 0; }
}

.music {
  display: flex;
  justify-content: center;
  margin-top: 1.5rem;
}

#spotify-btn {
  padding: 1rem 2rem;
  font-size: 1.2rem;
  border: none;
  border-radius: 30px;
  background: #a2d1b2; /* color verde Spotify */
  color: #fff;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 6px 15px rgba(0,0,0,0.1);
  transition: all 0.3s ease;
}

#spotify-btn:hover {
  background: #85d6a1;
  transform: scale(1.05);
}


/* =========================
   Responsive
========================= */

/* Para pantallas medianas (tablets ~768px) */
@media (max-width: 768px) {
  main {
    width: 95%;
    max-width: 600px;
  }

  .intro h2 {
    font-size: 1.8rem;
  }

  .intro p {
    font-size: 1.1rem;
  }

  .time-btn {
    padding: 1.2rem 2.2rem;
    font-size: 1.3rem;
  }

  .visual {
    height: 350px;
  }

  .motivational {
    font-size: 2rem;
    bottom: 130px;
  }

  #start-btn, #spotify-btn {
    font-size: 1.3rem;
    padding: 1.2rem 2.5rem;
  }
}

/* Para pantallas pequeñas (móviles ~480px) */
@media (max-width: 480px) {
  main {
    width: 98%;
    max-width: 100%;
  }

  .intro h2 {
    font-size: 1.5rem;
  }

  .intro p {
    font-size: 1rem;
  }

  .time-btn {
    padding: 1rem 1.5rem;
    font-size: 1.1rem;
  }

  .visual {
    height: 300px;
  }

  .motivational {
    font-size: 1.5rem;
    bottom: 110px;
  }

  #start-btn, #spotify-btn {
    font-size: 1.2rem;
    padding: 1rem 2rem;
  }

  .options {
    flex-direction: column;
    gap: 0.8rem;
    align-items: center;
  }
}

/* =========================
   Temporizador
========================= */
.timer {
  text-align: center;
  font-family: 'Poppins', sans-serif;
  font-weight: 700;
  font-size: 1.5rem;
  color: #ffffff;
  margin-top: 1rem;
  text-shadow: 0 2px 4px rgba(0,0,0,0.3);
  animation: fadeIn 1s ease-in-out;
}

@keyframes fadeIn {
  0% { opacity: 0; transform: translateY(-10px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* Respetamos animación de las frases motivacionales */
.motivational {
  position: absolute;
  bottom: 110px;
  width: 100%;
  text-align: center;
  font-family: 'Poppins', sans-serif;
  font-weight: 800;
  font-size: 1.8rem; 
  color: #fbf9fa;
  opacity: 0;
  animation: fadeInOut 6s ease-in-out infinite;
}

@keyframes fadeInOut {
  0%, 20% { opacity: 0; }
  30%, 70% { opacity: 1; }
  80%, 100% { opacity: 0; }
}